Experimental Study On The Stability Of Gypsum Mine Gob’s Dynamic Evolution Based On The Coupling Of Rheology And Disturbance

Gypsum mines which are mined by the room and pillar method, leave a great many ofmined-out areas, mechanism of large mined-out area caving is lack of interpretation systemtheory. In this paper, the rheological and disturbance coupling of the gypsum ore, thedynamic evolution law to the further “deterioration” of rock mechanics properties isresearched. Combined with the test and analysis of blasting vibration in the field, the effectof rheological single factor indoor, the rheological and disturbances coupling experiment andthe numerical simulation which used FLAC3D, to reveal the dynamic evolution mechanism ofthe gypsum mine goaf stability, lay the foundation for the safety management to themined-out areas of the gypsum mine, and has an important significance on long-term stabilityof underground space research.In order to provide a laboratory simulation of blasting vibration similar basis,-180munderground gypsum mine stope blasting vibration levels were tested and analyzed, get adifferent amount of explosives and blasting distance corresponding to a single segmentmaster oscillator frequency and peak vibration velocity, and regression analysis of thegypsum mine blasting vibration attenuation law, conclusions drawn from the above:To arrive at the room adjacent to mine the peak vibration velocity at the pillar and roof,pillar of blasting vibration to cause cumulative damage was provided.Experimental study on the role of rheological univariate, I performed gypsum oreuniaxial compression tests first, in order to determine a reasonable classification plasterspecimens loaded rheological test conditions under stress level classification. Analysis ofcreep curves under different conditions of stress level, static load at the moment being loaded,instantaneous deformation significantly increased, but the amount of change in the amplitudeof its growth before curing has been reduced stress levels in the larger, creep rupture strengthtests gypsum ore is about75to80percent uniaxial compressive strength.In order to study the rheological disturbances gypsum ore under the law of cumulativedamage coupling, according gypsum mine blasting vibration test data, bursting withhomemade device similar disturbances similar simulation by adjusting the outlet pressure of the air hammer to achiever different load disturbance intensity, obtained under differentstress levels and disturbed rock specimen disturbance intensity variation of the rheologicalcause damage, in order to achieve a similar disturbance simulation lab blast.Applying the same stress level by observing the impact of different loading conditionsand the same velocity variation plaster acoustic shock loads under different conditions ofstress levels, under the stress levels40to80percent of the compressive strength of thedisturbance load of0.4MPa to0.8MPa, corresponding to the amount of damage from the0.1026to0.3914, the measured velocity of sound waves to measure changes in the amount ofthe damage, gypsum ore cumulative damage has been changing with the speed of sound inseveral disturbances correspondence.Finally, I use FLAC3Dto simulate the gypsum mine stope by excavation and rheologicalmodel coupling perturbation displacement, stress and plastic zone in these areas, so it verifythe phenomenon that the debase of the gypsum ore stability due to the deterioration ofmechanical properties, proposed gypsum mine goaf disturbed rheological stability andlong-term exploitation of the impact of a larger blast.